Clausen Morten R, Christensen Kirstine L, Hedemann Mette S, Liu Ying, Purup Stig, Schmidt Mette, Callesen Henrik, Stagsted Jan, Bertram Hanne C
Department of Food Science, Science and Technology, Aarhus University, Aarslev, Denmark.
BMC Physiol. 2011 Aug 22;11:14. doi: 10.1186/1472-6793-11-14.
Pigs are widely used as models for human physiological changes in intervention studies, because of the close resemblance between human and porcine physiology and the high degree of experimental control when using an animal model. Cloned animals have, in principle, identical genotypes and possibly also phenotypes and this offer an extra level of experimental control which could possibly make them a desirable tool for intervention studies. Therefore, in the present study, we address how phenotype and phenotypic variation is affected by cloning, through comparison of cloned pigs and normal outbred pigs.
The metabolic phenotype of cloned pigs (n = 5) was for the first time elucidated by nuclear magnetic resonance (NMR)-based metabolomic analysis of multiple bio-fluids including plasma, bile and urine. The metabolic phenotype of the cloned pigs was compared with normal outbred pigs (n = 6) by multivariate data analysis, which revealed differences in the metabolic phenotypes. Plasma lactate was higher for cloned vs control pigs, while multiple metabolites were altered in the bile. However a lower inter-individual variability for cloned pigs compared with control pigs could not be established.
From the present study we conclude that cloned and normal outbred pigs are phenotypically different. However, it cannot be concluded that the use of cloned animals will reduce the inter-individual variation in intervention studies, though this is based on a limited number of animals.
在干预研究中,猪被广泛用作人类生理变化的模型,这是因为人类与猪的生理学特征极为相似,且使用动物模型时实验可控性高。原则上,克隆动物具有相同的基因型,可能也具有相同的表型,这为实验控制提供了更高水平,有可能使其成为干预研究的理想工具。因此,在本研究中,我们通过比较克隆猪和正常远交猪,探讨克隆对表型及表型变异的影响。
首次通过基于核磁共振(NMR)的代谢组学分析,对包括血浆、胆汁和尿液在内的多种生物流体进行分析,阐明了克隆猪(n = 5)的代谢表型。通过多变量数据分析,将克隆猪的代谢表型与正常远交猪(n = 6)进行比较,结果显示代谢表型存在差异。与对照猪相比,克隆猪的血浆乳酸水平更高,同时胆汁中的多种代谢物发生了改变。然而,与对照猪相比,克隆猪个体间变异性较低这一结论并未得到证实。
从本研究中我们得出结论,克隆猪和正常远交猪在表型上存在差异。然而,尽管本研究基于数量有限的动物,但不能得出使用克隆动物会减少干预研究中个体间变异的结论。